ChromoTek's Nano-Boosters are very small, highly specific binding proteins covalently coupled to bright and stable fluorescent dyes. These GFP-, RFP- and Vimentin- binding proteins are derived from single-domain alpaca antibody fragments termed VHHs or nanobodies.
- Higher image resolution
- Excellent performance in IF and super-resolution microscopy
- Stabilization, enhancement and reactivation of fluorescent signals
- Less than 2nm epitope-label displacement minimizes linkage error
- Monovalent, recombinant single domain antibody fragment from camelid
Nano-Boosters (also termed nanobody or VHH) are much smaller compared to conventional primary plus secondary antibodies (IgG complex). Due to their small size, VHHs are particular suitable for effective labelling with minimal fluorophore displacement for super-resolution microscopy. For relative comparison of the sizes of both affinity reagents see picture (right).
Wide-field vs. structured illumination microscopy (3D-SIM) of mid-stage intercellular bridge. The signal of CHMP4b-GFP (expressed under the endogenous promoter) is enhanced by the GFP-Booster. Microtubuli are stained with anti-tubulin antibody (pictures kindly provided by L. Schermelleh).
Tissue penetration rate
The comparison of conventional anti-GFP antibody and GFP-Booster shows the superior tissue penetration rate of GFP-Booster. Fluorescent images of transgenic mouse tissue expressing Cx3Cr1-EGFP. EGFP signal was enhanced either with conventional anti-GFP antibody conjugated to Alexa 647 (top image) or with the GFP-Booster_Atto647N (bottom image).
Central nervous system of a 3-day-old Drosophila larvae. GFP-Booster_ATTO488 was used to enhance the signal of dopamine neurons expressing GFP. (Image kindly provided by Kayvan Forouhesh Tehrani, the Kner Lab, University of Georgia; the Drosophila sample was supplied by the Shen lab, University of Georgia, Athens.)
Fluorescent proteins (FPs) are powerful tools to study protein localization and dynamics in
living cells. However, genetically encoded FPs have a number of disadvantages compared to chemical dyes:
- Signal intensities of fixed samples from cells expressing FP fusion at physiological expression levels are usually very low.
- Both photostability and quantum efficiency of FPs are generally not sufficient for
super-resolution microscopy (e.g. 3D-SIM, STED or STORM/ PALM).
- Many cell biological methods such as HCl treatment for BrdU-detection, the
EdU-Click-iT™ treatment or heat denaturation for FiSH lead to disruption of the FP signal.
In these cases, our Boosters will help you to get better images from your existing GFP/RFP expression constructs:
- VHHs do not cluster their epitopes
- Superior accessibility and labelling of epitopes in crowded cellular environments
- Atto and Abberior fluorophores conjugated to Nano-Boosters
- Consistent and reliable performance due to recombinant production
Find the right Nano-Booster: